In electronic devices such as servers and communication devices, daughter boards, which are circuit boards removably mounted in housings, have connectors concentrated at the front ends of the daughter boards in a direction in which the daughter boards are inserted. With this structure, since signal wires are routed through backplanes, which are boards disposed on surfaces of the housings toward which the daughter boards are inserted, the length of signal paths is increased. Also with this structure, the density of wiring on the daughter boards is increased, thereby increasing the number of daughter boards used in an electronic device and, accordingly, increasing the cost of the electronic devices.
In order to overcome these drawbacks, connectors are provided on a plurality of edges of the daughter board. When the daughter board has connectors on the plurality of edges thereof, the backplanes, which are boards on the housing side, are provided corresponding to the edges of the daughter board where the connectors are disposed.
When an electronic device has a plurality of backplanes connected to the plurality of edges of a daughter board as described above, the length of wiring on the daughter board from electronic components to the connectors may be decreased. This is useful for high-speed communication of a large number of signals. The above-described electronic device also allows the density of wiring on the daughter board to be decreased.
Specifically, the above-described connection structure uses a three-dimensional mounting structure in which backplanes are disposed on both side surfaces of the daughter board, or uses a structure in which a daughter board having been inserted into a housing is moved perpendicularly to the plane of the daughter board to connect the connectors on the backplane and the daughter board to each other. These connectors are disposed so as to be engageable in a direction perpendicular to the plane of the daughter board.
Japanese Laid-open Patent Publications No. 2006-164627, No. 50-119282, and No. 2002-223085 are examples of related art.